title: Phylogenetic study of plant Q-type C2H2 zinc finger proteins and expression analysis of poplar genes in response to osmotic, cold and mechanical stresses.
abstract: Plant Q-type C2H2 zinc finger transcription factors play an important role in plant tolerance to various environmental stresses such as drought, cold, osmotic stress, wounding and mechanical loading. To carry out an improved analysis of the specific role of each member of this subfamily in response to mechanical loading in poplar, we identified 16 two-fingered Q-type C2H2-predicted proteins from the poplar Phytozome database and compared their phylogenetic relationships with 152 two-fingered Q-type C2H2 protein sequences belonging to more than 50 species isolated from the NR protein database of NCBI. Phylogenetic analyses of these Q-type C2H2 proteins sequences classified them into two groups G1 and G2, and conserved motif distributions of interest were established. These two groups differed essentially in their signatures at the C-terminus of their two QALGGH DNA-binding domains. Two additional conserved motifs, MALEAL and LVDCHY, were found only in sequences from Group G1 or from Group G2, respectively. Functional significance of these phylogenetic divergences was assessed by studying transcript accumulation of six poplar C2H2 Q-type genes in responses to abiotic stresses; but no group specificity was found in any organ. Further expression analyses focused on PtaZFP1 and PtaZFP2, the two genes strongly induced by mechanical loading in poplars. The results revealed that these two genes were regulated by several signalling molecules including hydrogen peroxide and the phytohormone jasmonate.
authors.affiliation: Clermont Universite´, Universite´ Blaise Pascal, UMR 547 Physique et Physiologie Inte´gratives de l’Arbre Fruitier et Forestier, 24 avenue des Landais, BP 10448, 63177 Aubie`re Cedex, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Gourcilleau
authors.forename: Catherine
authors.initials: C
authors.lastname: Lenne
authors.forename: Claudia
authors.initials: C
authors.lastname: Armenise
authors.forename: Bruno
authors.initials: B
authors.lastname: Moulia
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Julien
authors.forename: Gisèle
authors.initials: G
authors.lastname: Bronner
authors.forename: Nathalie
authors.initials: N
authors.lastname: Leblanc-Fournier
mesh_terms: D003080:Cold Temperature; D017124:Conserved Sequence / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics; D009928:Organ Specificity / Q000235:genetics; D009995:Osmosis; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D032107:Populus / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013045:Species Specificity; D013314:Stress, Mechanical; D013997:Time Factors; D016335:Zinc Fingers / Q000235:genetics*
chemical_list: D010940:Plant Proteins; D012333:RNA, Messenger